Toxoplasma gondii is an obligate intracellular Apicomplexan parasite capable of invading and surviving within nucleated cells in most warm-blooded animals. This remarkable task is achieved through the delivery of effector proteins from the parasite into the parasitophorous vacuole and host cell cytosol that rewire host cellular pathways, facilitating parasite evasion of the immune system. Here, we have identified a novel export pathway in Toxoplasma that involves cleavage of effector proteins by the Golgi-resident aspartyl protease 5 (ASP5) prior to translocation into the host cell. We demonstrate that ASP5 cleaves a highly constrained amino acid motif that has some similarity to the PEXEL motif of Plasmodium parasites. We show that ASP5 can mature effectors at both the N- and C-terminal ends of proteins and is also required for the trafficking of proteins without this motif. Furthermore, we show that ASP5 controls establishment of the nanotubular network and is required for the efficient recruitment of host mitochondria to the parasitophorous vacuole membrane. Global assessment of host gene expression following infection reveals that ASP5-dependent pathways influence thousands of the transcriptional changes that Toxoplasma imparts on its host cell. This work characterizes the first identified machinery required for export of Toxoplasma effectors into the infected host cell. Overall design: Three groups of human foreskin fibroblasts are compared. Each group has 3 replicates giving a total of 9 samples. The first group of samples are infected with wild type (GRA16HA) Toxoplasma gondii, the second group with Asp5 knock-out Toxoplasma gondii, and the final group remain uninfected. All fibroblasts are generated from one donor sample.
An aspartyl protease defines a novel pathway for export of Toxoplasma proteins into the host cell.
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View SamplesActivation of the innate immune system leading to a persistent state of low-grade of tissue inflammation greatly influences the risk of developing metabolic complications associated with obesity. In this study, we characterized the inflammatory state in adipose tissue from obese patients and explored the potential of the specialized pro-resolving mediator (SPM) resolvin D1 (RvD1) to actively terminate inflammation and promote its resolution. By means of high-troughput transcritomic analysis we identified a cytokine-related molecular signature in obese omental adipose tissue, characterized by a remarkable overexpression of interleukin (IL)-6, IL-1 and IL-10 associated with a concomitant increase in macrophage infiltration, which gradually increased in a body mass index-dependent manner.
Signaling and Immunoresolving Actions of Resolvin D1 in Inflamed Human Visceral Adipose Tissue.
Specimen part, Disease stage
View SamplesWe used microarrays to detail the global programme of gene expression underlying cellularisation and identified distinct classes of up-regulated genes during this process.
Bone healing in an aged murine fracture model is characterized by sustained callus inflammation and decreased cell proliferation.
Specimen part
View SamplesThe unique metabolic profile of most cancers (aerobic glycolysis) might confer apoptosis-resistance and be therapeutically targeted. Compared to normal cells, several human cancers have high mitochondrial membrane potential and low expression of the K+ channel Kv1.5, both contributing to apoptosis-resistance. Dichloroacetate (DCA), an inhibitor of the mitochondrial pyruvate dehydrogenase kinase (PDK), shifts metabolism from glycolysis to glucose oxidation, decreases mitochondrial membrane potential, increases mitochondrial-H2O2 and activates Kv channels in all cancer, but not normal cells; DCA upregulates Kv1.5 by an NFAT1-dependent mechanism. DCA induces apoptosis, decreases proliferation and tumor growth in vitro and in vivo, without apparent toxicity. Molecular inhibition of PDK2 by siRNA mimics DCA. The mitochondria-NFAT-Kv axis and PDK are important therapeutic targets in cancer; the orally available DCA is a novel selective anticancer agent.
A mitochondria-K+ channel axis is suppressed in cancer and its normalization promotes apoptosis and inhibits cancer growth.
No sample metadata fields
View SamplesNon-proteolytic ubiquitin signaling mediated by K63 ubiquitin chains plays a critical role in multiple pathways converging on NFKB activation that are key to the development and activation of immune cells. However, a complete understanding of how the regulation of ubiquitin signaling affects immune cells development and functionality is still missing. G Protein Suppressor 2 (GPS2) is a multi-functional protein that recently emerged as an important regulator of inflammation and lipid metabolism through inhibition of Ubc13 activity. Here, we have deleted GPS2 in the B cell lineage results and performed RNAseq of WT and KO splenic B cells. Overall design: RNA-seq of WT and_KO of GPS2 in Bcells.
Inhibition of Ubc13-mediated Ubiquitination by GPS2 Regulates Multiple Stages of B Cell Development.
Specimen part, Subject
View SamplesOver the last years, evidence has grown that exposure to air pollution, in addition to impairing lung function and health in individuals of all age, can be linked to negative effects in newborn when present during pregnancy. Data suggests that intrauterine exposure of fetuses (exposure of the mother to air pollution during pregnancy) in fact exerts a negative impact on lung development. However, the means by which exposure during pregnancy affects lung development, have not been studied in depth yet. In this study, we investigated alterations of the transcriptome of the developing lung in a mouse model of gestational and early-life postnatal exposure to urban PM2.5 (from Sao Paulo, Brazil).
Pre- and postnatal exposure of mice to concentrated urban PM<sub>2.5</sub> decreases the number of alveoli and leads to altered lung function at an early stage of life.
Specimen part
View SamplesDynamic gene expression in the PSM of vertebrates is critical for the spatial and temporal patterning of somites.
Dynamic CREB family activity drives segmentation and posterior polarity specification in mammalian somitogenesis.
Specimen part
View SamplesPublic information is widely available at low cost to animals living in social groups. For instance, bystanders may eavesdrop on signaling interactions between conspecifics and use it to adapt their subsequent behavior towards the observed individuals. This social eavesdropping ability is expected to require specialized mechanisms such as social attention, which selects social information available for learning. To begin exploring the genetic basis of social eavesdropping, we used a previously established attention paradigm in the lab to study the brain gene expression profile of male zebrafish in relation to the attention they have paid towards conspecifics involved or not involved in agonistic interactions. Microarray gene chips were used to characterize their brain transcriptomes based on differential expression of single genes and gene sets. These analyses were complemented by promoter region-based techniques. Using data from both approaches, we further drafted protein interaction networks. Our results suggest that attentiveness towards conspecifics, whether interacting or not, activates pathways linked to neuronal plasticity and memory formation. The network analyses suggested that fos and jun are key players on this response, and that npas4a, nr4a1 and egr4 may also play an important role.
Brain Transcriptomic Response to Social Eavesdropping in Zebrafish (Danio rerio).
Sex, Specimen part, Treatment
View SamplesHistone acetylation and other modifications of the chromatin are important regulators of gene expression and, consequently, may contribute to drug-induced behaviors and neuroplasticity. Previous studies have shown that a reduction on histone deacetylase (HDAC) activity results on the enhancement of some psychostimulant-induced behaviors. In the present study, we extend those seminal findings by showing that the administration of the HDAC inhibitor sodium butyrate enhances morphine-induced locomotor sensitization and conditioned place preference. In contrast, this compound has no effects on the development of morphine tolerance and dependence. Similar effects were observed for cocaine and ethanol-induced behaviors. These behavioral changes were accompanied by a selective boosting of a component of the transcriptional program activated by chronic morphine administration that included circadian clock genes and other genes relevant in addictive behavior. Our results support an specific role for histone acetylation and the epigenetic modulation of transcription at a reduced number of biologically relevant loci on non-homeostatic, long lasting, drug-induced behavioral plasticity. To further investigate the molecular bases of sodium butyrate action on long-lasting behavioral responses to morphine, we screened for potential substrates of their interaction by performing a genome-wide comparison of the striatal transcriptome after chronic administration of morphine in the absence or presence of sodium butyrate.
Selective boosting of transcriptional and behavioral responses to drugs of abuse by histone deacetylase inhibition.
Sex, Age, Specimen part
View SamplesMethods of reprogramming somatic cells to an induced pluripotent state (iPSC) have enabled the direct modeling of human disease and ultimately promise to revolutionize regenerative medicine. iPSCs offer an invaluable source of patient-specific pluripotent stem cells for disease modeling, drug screening, toxicology tests and importantly for regenerative medicine, and already have been employed to unmask novel insights into human diseases. While iPSCs can be consistently generated through overexpression of the four Yamanaka Factors OCT4, SOX2, KLF4 and c-MYC (OSKM), reprogrammed cells present worrisome differences with embryonic stem cells in transcriptional and epigenetic profiles, as well as developmental potential and difficulties in cell culturing. A thorough mechanistic understanding of the reprogramming process is critical to overcoming these barriers to the clinical use of iPSC. We have recently published a novel factor combination based on molecules specifically enriched in the metaphase II human oocyte. We have shown that just the overexpression of histone-remodeling chaperone ASF1A and OCT4 in hADFs previously exposed to the oocyte-specific paracrine growth factor GDF9 can reprogram hADFs into pluripotent cells (AO9-iPSCs). Our study contributes to the understanding of the molecular pathways governing somatic cell reprogramming. Here we want to go deeper in the reprogramming mechanisms by understanding the importance of somatic cell origin, and analyzing (and establishing comparison with) the transcriptional and epigenetic characteristics of AO9-iPSCs. As the intrinsic histone chaperone activity of ASF1A and our data indicate, these cells could be closer to the embryonic pluripotent state, with less epigenetic memory, better culture properties and differentiation potential.
Analysis of Menstrual Blood Stromal Cells Reveals SOX15 Triggers Oocyte-Based Human Cell Reprogramming.
Sex, Specimen part, Subject
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